Scutibracon rugosus Samartsev, Duong & Long, 2025

Samartsev, Konstantin G., Duong, Tran Dinh & Long, Khuat Dang, 2025, The genus Scutibracon Quicke & Walker (Hymenoptera: Braconidae) in Vietnam, with new records and descriptions of two new species, Zootaxa 5715 (1), pp. 407-418 : 410-412

Scutibracon rugosus Samartsev, Duong & Long , sp. nov.

( Figs 13–24 )

Material. Holotype, Vietnam, Vinh Phuc Province, Phuc Yen City, Ngoc Thanh Commune, Me Linh Biodiversity Station , 21°23’03” N 105°42’40” E, h = 60 m, Malaise trap No 1 ( MT1 ), 20.v.2021 ( Tran Dinh Duong & Trinh Xuan Thanh), female (IB KS0004383 ) . Paratype, Vietnam, Hoa Binh Province, Da Bac District, Tuly Commune , road, bamboo, sweeping, 21.x.1990 ( S.A. Belokobylskij), 1 male ( ZISP INS _HYM_0002852) .

Diagnosis. S. rugosus sp. nov. differs from S. hispae and S. malabaricus by the widely glabrous median area of mesoscutum and other characters listed in the key couplet 3 below. The new species differs from S. gracillariae , S. fujianensis , and S. sumodani by the widely glabrous median area of mesoscutum and absence of the wide protruding lamella on the posterior margin of T4.

Description. Female. Body length 2.0 mm; fore wing length 2.0 mm.

Head. Width of head (dorsal view) 2.0 × its median length. Transverse diameter of eye (dorsal view) 2.4 × as long as temple. OOL 2.6 × OD; POL 1.0 × OD; OOL 2.6 × POL. Frons flat, with shallow mid-longitudinal groove. Longitudinal diameter of eye in lateral view 1.3 × its transverse diameter, transverse diameter of eye 3.1 × minimum width of temple, hind margins of eye and temple broadened ventrally. Face width 1.4 × combined height of face and clypeus, 2.7 × width of hypoclypeal depression. Width of hypoclypeal depression 0.9 × distance from depression to eye. Intertentorial distance 1.6 × tentorio-ocular distance. Height of clypeus 0.4 × width of hypoclypeal depression. Longitudinal diameter of eye 2.2 × as long as malar space (front view). Maxillary palp as long as eye height.

Antenna with 21 antennomeres, 1.1 × as long as fore wing. First flagellomere 2.4 × as long as its apical width, middle and penultimate flagellomeres 2.3 × and 2.5 × as long as wide, respectively.

Mesosoma 1.3 × as long as its maximum height. Transverse pronotal sulcus deep and crenulate. Width of mesoscutum 1.4 × its median length (dorsal view). Notauli deep anteriorly, shallow and not united posteriorly. Mesoscutum setose on notaulic area and laterally, widely glabrous medially. Scutellar sulcus 0.15 × as long as scutellum. Mesepimeral sulcus smooth, mesopleural pit deep. Median area of metanotum with incomplete median carina. Metapleural sulcus crenulate. Propodeal spiracle oval, located behind middle of propodeum, weakly protruding. Mid-longitudinal keel on propodeum complete, with weakly crenulate margin, in upper half within deep crenulate mid-longitudinal impression.

Fore wing. Angle between veins C+SC+R and 1-SR 70–75°. Vein r arising from basal 0.4 of pterostigma. Vein 1-R1 1.9 × as long as pterostigma. Marginal cell 10 × as long as distance from its apex to apex of wing. Vein 3-SR 1.5 × vein r, 0.25 × vein SR1, 1.2 × vein 2-SR. Vein 1-M 0.8 × vein 1-SR+M, 1.9 × vein m-cu, 2.1 × vein cu-a. Vein cu-a interstitial. Vein 2-SR+M 0.4 × vein 2-SR, 0.6 × vein m-cu.

Legs. Hind femur 3.5 × as long as wide. Hind tibia 1.5 × as long as hind femur, 7.4 × as long as wide, its inner spur 0.35 × as long as hind basitarsus. Hind tarsus almost as long as hind tibia, 0.8 × as long as mesosoma. Fifth segment of hind tarsus 0.5 × as long as hind basitarsus and 0.75 × as long as second segment. Claws with shortly protruding and blunt basal lobes.

Metasoma with 4 dorsally visible tergites. Median length of T1 0.6 × its apical width. Dorsal carinae of T1 complete, sublateral carinae absent. Posterior width of T1 1.1 × median length of T2. T2 medially 1.2 × as long as T3. Anterior width of T2 1.2 × its median length. Median area of T2 very narrow, keel-like, widened anteriorly, extending in incomplete longitudinal carina. T2 with long, strongly converging sublateral carinae. Anterolateral areas of T2 indistinct. Spiracle of T2 located at middle of tergite, in its dorsum. Suture between T2 and T3 weakly curved. Posterior margins of T3 and T4 with deep smooth transverse subapical grooves. Ovipositor sheath 0.3 × as long as hind tibia and 0.1 × as long as fore wing. Apex of ovipositor simple, acute, with weak ventral serration.

Sculpture. Body mostly smooth. Propodeum with short rugae along posterior margin. T1 laterally rugose, its median area posteriorly rugose. T2 areolate-rugose to rugose, T3 longitudinally rugose, T4 irregularly punctate to granulate, T5 and T6 almost smooth.

Colour. Scape yellowish brown, flagellum yellowish brown and apically darkening. Head and mesosoma mostly yellowish brown with weakly brownish darkened gena along posterior margin of eye, median lobe of mesoscutum, ventral side of propleuron, and posterior margin of propodeum. Mouth parts, tegulae and legs mostly pale yellow. Pterostigma and wing veins yellowish brown, wing membrane weakly darkened. Metasoma pale yellow with large dark brown patch occupying posterior margin of T2 and most of T3.

Male. Body length 1.7 mm; fore wing length 1.5 mm. Transverse diameter of eye (dorsal view) 2.8 × as long as temple. OOL 2.0 × OD; POL 0.9 × OD; OOL 2.2 × POL. Transverse diameter of eye (lateral view) 3.5 × minimum width of temple. Face width 1.3 × combined height of face and clypeus; 2.4 × width of hypoclypeal depression. Width of hypoclypeal depression 1.1 × distance from depression to eye. Longitudinal diameter of eye 3.0 × as long as malar space (front view). Antenna with 19 antennomeres. First flagellomere 2.6 × as long as its apical width, middle and penultimate flagellomeres 2.4 × and 2.9 × as long as wide, respectively. Scutellar sulcus 0.25 × as long as scutellum. Angle between veins C+SC+R and 1-SR 65–70°. Marginal cell 16 × as long as distance from its apex to apex of wing. Vein 3-SR 1.0 × vein 2-SR. Vein 1-M 2.8 × vein cu-a. Hind femur 3.7 × as long as wide. Hind tarsus 1.1 × as long as hind tibia. Median length of T1 0.9 × its apical width. Posterior width of T1 0.8 × median length of T2. T2 medially 1.4 × as long as T3. Ground colour of metasoma yellow and not pale yellow. Otherwise similar to female.

Etymology. The species epithet “ rugosus ” is given referring to the coarse rugose sculpture of the metasoma.

Distribution. Vietnam.

Figures

FIGURES 13–24. Scutibracon rugosus sp. nov. (holotype, female, IB); 13—habitus, lateral view; 14—head, front view; 15— head, dorsal view; 16—apex of hind tarsus; 17—hind tarsus; 18—head, lateral view; 19—mesosoma, dorsal view; 20—wings; 21—propodeum and T1, dorsolateral view; 22—propodeum and metasoma, dorsal view; 23—mesosoma, lateral view; 24—T3– T6, dorsolateral view. Scale bars: 1.0 mm (13); 0.25 mm (14–19, 21, 24); 0.5 mm (20, 22, 23).